The present disclosure relates to downhole tools and, more particularly, to ball valves used in subterranean well systems.
A ball valve is a type of fluid flow valve that uses a spherical ball as a closure mechanism. The ball portion of the ball valve has a hole or through bore defined at least partially therethrough that aligns with the direction of fluid flow when the ball valve is opened and misaligns with the direction of fluid flow when the ball valve is closed. Ball valves have many applications in downhole tools for use in a wellbore, such as formation tester valves and safety valves. Ball valves are used in many wellbore operations since ball valves can provide a large through bore that allows for the passage of tools, tubing strings, and high-volume fluid flow. Ball valves are also compactly arranged. For example, ball valves typically have a cylindrical outer profile that corresponds to the cylindrical outer profile of the remainder of a tool string that carries the ball valve into the wellbore and therefore presents few or no protrusions to hang up on the interior of the well.
Some wellbore operations require downhole tools that are rated to the highest performance standards of the International Organization for Standardization (ISO). For instance, some downhole tools, such as packers and bridge plugs, must be V0 (“V-not”) rated, which corresponds to the ISO 14310-V0 standard and consists of the highest or strongest industry validation. A ball valve that is V0 rated consists of a ball valve that can be used in a downhole environment and remains gas tight and bubble free during operation.